In the past, as a technology for detecting information regarding cycling of a bike, a technology of detecting a rotation rate of a pedal is known. For example, Patent Literature 1 discloses a technology in which a crank rotation sensor is attached to a chain stay of a bike, which faces a pedal, a magnet is attached to the pedal, and a magnetic field line of the magnet which revolves in accordance with rotation of the pedal is detected for each revolution of the crank. Patent Literature 1 describes that a detection value of the crank rotation sensor is transmitted to a display apparatus, or the like, using a wireless communication apparatus. Further, Patent Literature 2 discloses a technology in which a rotation rate of a pedal is detected using angular velocity detected by an angular velocity sensor attached to a bike.